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Donor challenge:
Your donation will be matched 2-to-1 right now. Your $5 gift becomes $15!
Dear Internet Archive Community,
I’ll get right to it: please support the Internet Archive today. Right now, we have a 2-to-1 Matching Gift Campaign, so you can triple your impact, but time is running out!The average donation is $45. If everyone reading this chips in just $5, we can keep this website going for free, and free of ads. That's right, all we need is the price of a paperback book to sustain a non-profit website the whole world depends on. For 23 years this has been my dream: for a generation of learners who turn to their screens for answers, I want to put the very best information at their fingertips. We stand with Wikipedians, librarians and creators to provide enduring access to the world’s most trustworthy knowledge. We’re dedicated to reader privacy so we never track you. We don’t accept ads. But we still need to pay for servers and staff. The Internet Archive is a bargain, but we need your help. If you find our site useful, we ask you humbly, please chip in. Thank you.
—Brewster Kahle, Founder, Internet Archive
Donor challenge:
Your donation will be matched 2-to-1 right now. Your $5 gift becomes $15!
Dear Internet Archive Community,
I’ll get right to it: please support the Internet Archive today. Right now, we have a 2-to-1 Matching Gift Campaign, so you can triple your impact, but time is running out!The average donation is $45. If everyone reading this chips in just $5, we can keep this website going for free, and free of ads. That's right, all we need is the price of a paperback book to sustain a non-profit website the whole world depends on. For 23 years this has been my dream: for a generation of learners who turn to their screens for answers, I want to put the very best information at their fingertips. We stand with Wikipedians, librarians and creators to provide enduring access to the world’s most trustworthy knowledge. We’re dedicated to reader privacy so we never track you. We don’t accept ads. But we still need to pay for servers and staff. The Internet Archive is a bargain, but we need your help. If you find our site useful, we ask you humbly, please chip in. Thank you.
—Brewster Kahle, Founder, Internet Archive
Donor challenge:
Your donation will be matched 2-to-1 right now. Your $5 gift becomes $15!
Dear Internet Archive Community,
I’ll get right to it: please support the Internet Archive today. Right now, we have a 2-to-1 Matching Gift Campaign, so you can triple your impact, but time is running out!The average donation is $45. If everyone reading this chips in just $5, we can keep this website going for free, and free of ads. That's right, all we need is the price of a paperback book to sustain a non-profit website the whole world depends on. For 23 years this has been my dream: for a generation of learners who turn to their screens for answers, I want to put the very best information at their fingertips. We’re dedicated to reader privacy so we never track you. We don’t accept ads. But we still need to pay for servers and staff. If you find our site useful, we ask you humbly, please chip in. Thank you.
—Brewster Kahle, Founder, Internet Archive
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Rara arithmetica; a catalogue of the arithmetics written before the year MDCI, with description of those in the library of George Arthur Plimpton, of New York
Rara arithmetica; a catalogue of the arithmetics written before the year MDCI, with description of those in the library of George Arthur Plimpton, of New York
![[WorldCat (this item)]](/images/worldcat-small.png "[WorldCat (this item)]")